Scottish Independence: Scotland would become independent on 24 March 2016, says Nicola Sturgeon

The putative date announced by Deputy First Minister Nicola Sturgeon marks the anniversary of both the Union of the Crowns in 1603 and of the signing of the Acts of Union in 1707 (PA)

Scotland's anti-independence campaign maintains a notable lead in poll results released on Sunday, ahead of next year's referendum.

The results, from a Panelbase survey for The Sunday Times and Real Radio Scotland, come on the day that the country's Deputy First Minister announced the day Scotland will break away from the United Kingdom, should its people back independence.

Nicola Sturgeon announced the date - 24 March 2016 - ahead of Tuesday's launch for the "landmark" white paper from the Scottish government, a 670-page document setting out the Nationalists' case.

The vote will take place on 18 September next year. Those against the breakaway have said stipulating a date by which all formalities must be complete would put the Nationalists in an awkward position if they win the vote.

The poll put support for a Yes vote at 38 per cent, with those backing a No vote at 47 per cent. A total of 15 per cent said they did not know which way they would go.

Pro-independence campaigners said the poll shows they need less than a five point swing to take the lead.

Announcing the prospective date of independence, Sturgeon said: "This guide to an independent Scotland will be the most comprehensive and detailed blueprint of its kind ever published, not just for Scotland but for any prospective independent country.

"It is a landmark document which sets out the economic, social and democratic case for independence."

She urged members of the Scottish public to pick up a copy and read it. It will include details on economic growth, gender equality in employment, and what she described as a "decent minimum wage."

The proposed Independence Day follows the dissolution of the current Scottish Parliament, on 23 March 2016.

It would also mark the anniversary of both the Union of the Crowns in 1603 and of the signing of the Acts of Union in 1707.

The government has initially printed 20,000 copies of the paper, which will be made available to everyone who requests a copy.

A spokesman for the Scotland Office said: "Naming the date of independence ahead of a referendum result would only weaken the Scottish Government's negotiating position if Scotland voted to leave the UK.

"People in Scotland still don't know the full terms the Scottish Government would try to negotiate but the 28 members of the EU, Nato and the rest of the UK would all know that for the Scottish Government the date is more important than the deal.

He added that the Government is "confident the case for staying in the UK is far stronger than the untested, uncosted and unconvincing claims the Scottish government have made to date."

And a spokesman for Better Together, which campaigns for a "No" vote in the referendum, said: "This is the worst negotiating tactic possible. What the nationalists have done is announce to everybody who they would have to enter into talks with if we go it alone, the date where everything must be settled by.

"It doesn't exactly put them in a strong bargaining position."